Domestic appliances for heating water or making hot beverages usually come in a form of kettles, coffee percolators or similar apparatus. While such domestic appliances provide useful utility, they can be harmful and potentially dangerous to the user because of the heated fluid they carry. Other potentially harmful appliances to a user exist in the form of toasters, blenders, etc. with a hot exterior which can harm a user if they are unaware of the operative state of the appliance.
On the majority of such appliances, some visual indication is provided for the status of the appliance as to whether the appliance is switched on or off. This is particularly important on apparatus such as coffee percolators where there is a likelihood that the apparatus will not only produce the beverage but also maintain the beverage on a heated plate for use over a period of time.
The usual method for indicating the status of the appliance is to provide some kind of visual indication being either the position of the off-on switch or, on many appliances, an indicating light. However, such indicating lights are generally given by small low-powered lamps provided on one side of the apparatus and may not always be apparent to a user or, sometimes, the lamps are just not conspicuous enough as low-wattage lamps are always preferred to minimize non-critical energy consumption. This increases the likelihood of the apparatus being left onto either damage the apparatus or catch a user unawares, such as a user may find themselves on a heated portion of the apparatus without appreciating that the apparatus was on.
For example, in the case of kettles or similar, it may be desirable to know when the kettle has achieved a desired temperature. Most such appliance which is purely for heating water for making a beverage will have some form of automatic cut-off, generally relying on a steam-operated switch or similar. However, the operation of that switch does not provide much of an indication to a user that the state of the apparatus has changed and that the water has achieved the desired temperature. Unless the user specifically notes the position of the switch or hears a small audible click once the switch activates, there is little other provision of indicators. Again, a small indicating light could be provided although this also depends on the positioning of the light and once the risk of not being particularly apparent to a user at a distance or from a side of the appliance that masks the indicating light itself.
Other domestic appliances such as toasters or blenders may also benefit from a more visible indication of the operative state of the appliance to avoid harm to a user that is unaware the appliance is on.
It may be desirable to provide a further form of indication which, if possible, can also add to the aesthetic appearance of the appliances by providing a new visual effect. Preferably, such an indication carries with it practical utility.